Domestic coal stoker



y 1939- P. FRICCHIONE DOMESTIC COAL STOKER Filed April 28, 1937 2 Sheets-Sheet 1 July 11, p FR|H|QNE 2,165,627

' v 1 DOMESTIC COAL STOKER Filed April 28, 1937 5 M55 Q 2 m v Patented July 11, 1939 UNITED STATES PATENT OFFICE 2,165,627 DOMESTIC con. s'roxan Pasquale Fricchione, Scranton, Pa. Application April as, 1937, Serial No. 139,576 9 Claims; (01. 198-213) My invention relates to mechanical stokers of the underfeed type, and more particularly to a stoker arrangement adapted for use with domestic coal burning furnaces. i

Heretofore it has been proposed to provide mechanical stoker devices, for domestic purposes,

wherein the coal or other fuel is conveyed from a source of supply by means of a screw conveyor, the coal being introduced at the bottom of the burner. It has also been proposed to provide ash removal devices associated with the structure, for the purpose of automatically removing ashes, dust and the like after the coal or other fuel has been consumed. In all of the i prior art devices, of which I am aware, the fuel feeding and ash removal arrangements, together with the cooperative elements of the stoker organization, are ofirathe'r complicated design,

requiring a considerable number of parts, ex-

)tensive alteration of the furnace structure to.v

permit of installation, and a substantial amount of supervision in order to insure reasonably satisfactory operation.

While the prior art arrangements will no doubt Ii function for their intended purposes, they are resultant discontinuous or intermittent feeding of coal to the burner. Another difliculty which sometimes arises, in connection with the opera- ,tion of these devices, is failure of the ash ie-- w moval arrangement to function properly, for the purpose of emciently'removing the ashes after the coal or other fuel has been consumed, with the result that the ashes, dust and the like, builds ,up around the burner parts and seriously interferes with their proper operation.

The present invention, therefore, is designed to overcome the above enumerated deficiencies, as well as others, of. the prior art-structures, by providing an improved mechanical stoker for domestic purposes, wherein the fuel is fed to the burner in a substantially continuous volume at all times during operation of the machine, the ashes and-other portions of the products of combustion being simultaneously removed from the vicinity of the burner, in such fashion as to prevent accumulation of ashes and interference with any of the moving parts of the burner or stoker mechanism.

An object of my invention is to provide a I mechanical stoker having an improved fuel feeding arrangement, designed to supply a substantially continuous volume of fuel to the furnace during normal operation.

Another object of my invention is to provide a mechanical stoker having an improved ash re- 5 moval device adapted to efliciently remove ashes, dust and the like, from the vicinity of the burner after the fuel has been consumed.

Yet another object of my invention is to prof vide a simplified and improved driving means 10 for the movable or operating parts of the stoker.-

Still another object of my invention is to provide a mechanical stoker adapted for use with a fuel hopper type of coal supply or one that may be supplied directly from a coal bin or other domestic storage container;

A further object of my invention is to provide an improved mechanical stoker for domestic purposes, consisting of but few parts which are of easy access for cleaning and inspection purposes and one that is not, liable to get out of order even after long and continued use.

With these and other objects in view, which may be incident to my improvements, the invention consists in the parts and combinations to 5 be hereinafter set forth and claimed, with the understanding that the several necessary elements, comprising my invention, may be varied in construction, proportions and arrangement, without departing from the spirit and scope of the appended claims.

In order to make my invention more clearly understood, I have shown in the accompanying drawing means for carrying the same into practical efiect', without limiting the improvements 5 in their useful applications to the particular constructions, which for the purpose of explanation, have been made the subject of illustration.

In the drawings:

Figure 1 is aside elevational view having 40 parts thereof in section, showing details of the arrangement of certainelements of the machine.

Fig. 2 is a plan view of the arrangement shown in Figure 1.

Fig. 3 is an elevational view of a modification, having parts thereof shown in section. Fig. 4 is a plan view of the arrangement shown in Fig. 3.

Fig. 5 is a bottom plan view of the rotatable gear member to which the ash scrapers are at- 5 means.

Referring to the drawings and'more particularly to Figures 1 and 2 thereof, I have shown one form of my improved stoker arrangement comprising a burner or fire pot, designated generally by numeral l, a fuel supply conduit 2, having a screw conveyor 3 mounted therein, and an air supply conduit 4 extending between the bottom of the burner and a source of supply of air. The burner or retort I may be of conventional type and comprises a series of tuyeres or rings 5 arranged within a shell 6, the shell being supported through the medium of a crown plate I, bolted or otherwise attached to an extension 8 formed on air supply conduit 4.

In connection with the arrangement of the shell 6, tuyeres 5, and crown plate 1, it will be noted that the crown plate is constructed and arranged with respect to extended portion 8, so that a peripheral groove or recess 9 is formed between the crown plate and the extension, the peripheral groove being adapted to receive the position within the recess by means of suitable bolts Ill adapted to thread into enlarged portion I I formed in the body of the shell.

Below the crown plate, a rotatable ring or sprocket member I2 is provided, the ring being formed with a plurality of arms l3 suitably mounted with respect to the retort whereby upon rotation of ring l2, the vertical portions ll of the arms contact with ashes at the top of the burner and remove the same from the-vicinity of the periphery of the top ring l5. The under side of ring I2 is provided with a plurality of spaced projections l6, as more clearly shown in Fig. 5. These projections are suitably spaced, that is, the distances between the centers of the projections are such that ashes, dust or the like, in the vicinity of the base of the burner, are preventedfrom filling the spaces between projections, thus eliminating interference with rotation of the ring by means of gear or sprocket member II.

It will be appreciated that in the use of burners of the underfeed type, ashes which are removed from the top of the burner collect in the vicinity of the bottom of the-burner and tend to build up around the fuel and air supply conduits as well as around the exposed movable members. In

order to decrease friction and to eliminate as far as possible any interference with proper operation of the rotating parts, *I have provided an improved form of mounting for ring gear member l2 whereby the tendency of the ashes to collect on the bearing surfaces and interfere with freedom of movement of the parts is substantially eliminated. To. this end, extension member 3, upon which ring gear I2 is rotatably mounted, is formed with a peripheral flange member I! adapted to form a seat or bearing surface for a plurality of projections l9 which may be formed integrally with the body portion of the ring member. Projections I! are adapted to rest upon perlpheral flange l8 and are suitably spaced so that the ashes which may collect on the upper surfaces of the flange, are pushed forwardly during rotation of ring member I2, thus maintaining the bearing surface clear of ashes and dust during operation of the device.

This arrangement is a decided improvement over conventional forms of mountings for the ring gear element, wherein ball hearings or rollers are used. It has been found, with the use of ball bearings, rollers and the like, that the ashes build a pin member 32.

ther modification of the conveyor connecting up around the bearing surfaces and even when the trackway or guides for the rollers areprotected, dust penetrates the small openings, which is blown or otherwise forced therein by the fan or other source of air supply. Small particles of dust or other foreign matter adhering to the bearing surfaces, causes the ring gear to raise or lift at certain points of its travel, with the result that it tends to bind at its points of support with resultant increase of friction which may be sufficient to resist normal movement of the ring to the extent that rotation thereof is practically stopped.

To further assist in leveling and distributing the ashes and other residue which accumulates in the vicinity of the base of the burner, ring gear I2 is provided with diametrically opposite spaced projections l9, adapted during rotation of the ring to push the ashes forwardly and circumferentially of the mound in which they are normally deposited to a position in which they can be picked up by the ash removal device, as will be described hereinafter.

The base or bottom portion 20 of the burner is formed as an extension of the fuel conduit 2, a reduced portion 2| thereof, providing a bearing support for screw conveyor shaft extension 22, to which gear or sprocket member I1 is attached. It will be understood that when rotation is imparted to screw conveyor 3, the conveyor shaft extension '22 is rotated and gear II which is adapted to mesh with projections l6 formed on the underside of ring gear l2, rotates therewith and imparts a rotative step-by-step movement to ring gear l2, thus causing vertical portions ll of arms l3 to move relatively to the periphery of ring ii, for the purpose of removing ashes, clinkers and the like which may overhang the top ring of the retort. I

For the purpose of driving screw conveyor 3, the air supply means and other moving parts of the stoker, there is provided a motor 23 and drive, mechanism comprising a gear box 24 having a plurality of gears mounted therein, together with its associated driving elements. It will be noted that the gear box is mounted between sections of the fuel supply conduit, that is, between conduit 2 and 2', the latter extending to a source of fuel supply, not shown. Gear member 25, which extends transversely of the gear box, is provided with a suitable pulley, not shown, positioned and arranged in line with pulley 26 formed on the shaft of motor 23, whereby gear 25 is driven. In mesh with gear 25 is a gear member 2] having a body portion 28 formed with an opening 29 concentric with the fuel supply conduits. The body portion 23, which is in the form of a rotatable sleeve, is provided with an extension 30 having a sprocket 3| formed thereon and that portion of the extension 33, intermediate the side of the gear box and sprocket 3| is formed with two diametrically opposite openings adapted to receive By means of the pin member, shafts 3' of the fuel conveyor are connected to the sleeve forming the body portion of gear 2.1, whereby rotation of the gear imparts rotative movement to the screw conveyor sections mounted in fuel conveyor conduits 2- and 2'. A suitable bearing 33 may be provided within the gear box, to form a bearing support for sleeve 28, which is formed with gear 21 on its periphery.

Drive motor 23 is mounted upon a suitable support 34, to the side or rear of which is positioned a blower or fan housing 35 having a breather 36 attached thereto, for the purpose of preventing the coal gas from the retort or burner I from backing up into the room wherein the stoker is installed. The motor shaft 31 is extended through the motor housing to provide a connection for the fan or blower and also for pulley 26 used to drive gear member 25.

In order to remove the ashes which accumulate in the vicinity of the base of the burner, an ash removal attachment for the stoker arrangement is provided. The ash removal device comprises a conduit 38 having a screw conveyor 39 rotatably mounted therein. Conduit 38 extends upwardly from the bottom of the burner to a point above the plane of the top of motor platform 34 and is provided with an opening 40 adapted to receive the ashes which accumulate at the bottom of the burner. The position of the conduit and more particularly the opening 49 is so designed that ashes which are pushed'forwardly of the flange l8 formed on projection Band those moved ahead of projections l9 are caused to fall into the open ng, thus keeping the space in the vicinity of sprocket l1 clear of ashes and other res'due at all times.

The upper end of the ash removal conduit is provided with a suitable discharge spout 4| having two branches 42 and 43 to which suitable ash receivers may be attached. Motion is imparted to the ash removal conveyor through the medium of sprocket 3!, chain member 44 and sprocket 45. For the purpose of providing for angular adjustment of the ash removal conduit and to enable ready displacement and positoning thereof, a universal joint, designated generally by numeral 46 is provided for connecting the conveyor shaft 39' with the stub shaft 41 upon which sprocket member 45 is mounted. The ash removal condut may be held and supported in the operative position by means of a suitable clamp or other fastening device 48, attached to the housing of the a r supply conduit by means of a bolt or screw 49, and also by a bracket member 48',

In the operation of the device so far described, coal is introduced through conduit 2 and is moved forwardly in the direction of the base of the *burner by means of the fuel conveyor 3'. When the fuel reaches the end of the conduit, it is forced upwardly of the bottom of the retort or burner until it reaches the zone of combustion near the top of the burner. Rotation of the screw conveyor imparts movement to sprocket II, which in turn rotates ring gear l2, to which the ash breakers or scrapers l4 are attached. After the coal hasbeen consumed, the ashes are pushed upwardly and spread out over plate l until they fall off or are knocked loose by means of the breaker arms. The ashes which drop to the base of the burnerare picked 41p by the ash removal conveyor 39 and carried along ash conduit 38 an-l ctscharged through one orboth of the discharge openings 42 or 43 into containers attached to those openings. 7

While the above described arrangement is designed primarily for an installationwhere n the source of fuel is the usual bin or storage compartment used for'domestic purposes, the device is also adapted for use with a hopper type of fu-l supply. For this purpose, a fuel supply chamber or compartment 50 is provided between gear box 24 and the end of the fuel supply condu t 2. Compartment 50 is equipped with a detachabc cover member 5|, which may be removed and a hopper or coal storage magaz ne of conventional type mounted on top of the compartment.

It will be noted that in my stoker arrangement, the fuel is conveyed from the source of supply, for example a bin to which conduit 2' is at tached, in a straight line from the source of supply to the burner. By means of the construction and design of rotatable sleeve 28, forming body portion of gear 21, the fuel is enabled to pass directly from conduit 2' through the body portion of the gear and into conduit 2 without interruption or deflection as would be encountered in the use of typical gear box arrangement wherein the main drive gear is positioned in the bottom of the box. The parts of my stoker arrangement are accessible for cleaning and inspection purposes and the device is designed to operate with minimum attention, In this connection, it will be noted that the conveyor sections, for example. may be easily removed from their respective conduits, Shaft 3' may be qu ckly disconnected and removed from conduit 2 by simply sliding sleeve member 52 along the axis of conduit 2', thus exposing connectors 53, which may be readily detached from the shaft so that the conveyor, may be withdrawn. Similarly the section of the fuel conveyor rotatably mounted in conduit 2 may be taken out by removing sprocket l1 and withdrawing the conveyor after shaft 3 has been disconnected. 7

Referring to Figs. 3 and 4, there is shown a modified form of the stoker arrangement wherein a different type of drive mechanism is used in connection with the fuel conveyor, fan and the ash removal device. The burner structure, screw conveyors for the fuel supply and ash removal and other parts of the device associated therewith are the same as those shown in Figure 1. In the modification, fuel conveyor 3 is adapted to be rotated by means of a sleeve member 54, rotatably mounted between compartment 50 and portion 55 forming part of the support or platform 34 upon which motor 23 is mounted. The rotatable sleeve 54 is provided with a gear member 56 adapted to be driven by means of a chain 51 at-' tached to gear 58 mounted upon the end of shaft 59. A gear box 60 mounted upon platform 34 is provided with a plurality of gears adapted to provide the required gear reduction ratio to drive the conveyors and other operat ng parts at the desired speed.

One of the gears positioned within the gear box,

is provided with a shaft 6| having a pulley 62 mounted thereon, movement of the gear shaft being obtained by means of belt 62', which connects pulleys 26 and 62. Shaft 6| may be extended through the gear box and attached to the fan or blower in a manner similar to the motor shaft 31, as shown in Figure 1. The ash removal conveyor is driven through the medium of chain 54 which is connected with asprbcket mounted at the end of shaft 59.

Referring to Figs. 6 and 7, there are shown modified forms of connecting sleeves and means for connecting the sleeves and the screw conveyor shafts. In Fig. 6, the sleeve member 63 is provided with an interior spiral 64 and the ends of the sleeve are provided with diametrically opposite openings adapted to receive pins 32. By means of this arrangement, the coupling between the parts is considerably simplified for certain types'of installations and by providing an interior spiral on the rotatable sleeve, a more uniform feed of fuel is obtained. In Figure 7, a further modification of the rotatable sleeve and means for connecting the sleeve and screw conveyor shaft is shown. In this arrangement, rotatable sleeve' 65 is mounted upon a bushing or sleeve 66 attached to the body portion of the fuel conduit by means of bolts or screws 61. The fuel conveyor shaft 3' is connected to the rotatable sleeve by means of pin member 32. In connection with these modifications, it will be understood that they are intended as substitutes for the rotatable sleeve 54 and connecting means used to connect the sleeve with the conveyorshaft as shown in Fig. 3.

While I have shown and described the preferred embodiment of my invention, I wish it to be understood that I do not confine myself to the precise details of construction herein set forth, by way of illustrations as it is apparent that many changes and variations may be made therein, by those skilled in the art, without departing from the spirit of the invention, or exceeding the scope of the appended claims.

What I claim is:

1. In a stoker of the underfeed type, a fuel conveying conduit formed of a plurality of sections, means to connect said sections to form a horizontal substantially continuous passage for the fuel, comprising a plurality of sleeve members, one of said sleeves being rotatably mounted in the fuel conduit, drive means on the periphery of the rotatable sleeve, a screw conveyor in the fuel conduit, means to connect the conveyor with the rotatable sleeve comprising a pin member insertable through the sleeve-and conveyor shaft and a source of power adapted to rotate the sleeve.

2. In a stoker of the underfeed type, a fuel conveying conduit formed of a plurality of sections, means to connect said sections to form a continuous passage for the fuel, a screw conveyor in said conduit, a gear box having gears therein positioned intermediate of the ends of the conduit, one of the gears having an opening in its body portion concentric with the fuel supply conduit, means insertable through the body portion of the gear and the conveyor shaft to connect said gear with the screw conveyor and a source of power adapted to rotate the gears.

3. In a stoker of the underfeed type. a fuel conveying conduit formed of a plurality of sections, means to connect said sections to form a continuous passage for the fuel, a screw conveyor in said conduit, a gear box having gears therein positioned intermediate of the ends of the conduit, one of the gears being formed with a body portion co-extensive with the width of the gear box, said gear having an opening in its body portion concentric with the fuel supply conduit,

means insertable through the body portion of the gear and the conveyor shaft to connect said gear with the screw conveyor and a source of power adapted to rotate the gears.

4. In a stoker of the underfeed type, a fuelthe fuel supply conduit, means insertable through the extension of the body portion and the conveyor shaft to connect the extended portion of said body of the gear with the screw conveyor and a source of power adapted to rotate the gears.

5. In a stoker of the underfeed type, a fuel conveying conduit formed of a pluralitv of sections, means to connect said sections to form. a continuous passage for the fuel, a screw conveyor in said conduit, a gear box having gears therein positioned intermediate of the ends of the conduit, one of the gears being formed with a body portion co-extensive with the width of the gear box and having an extension formed integrally therewith projecting beyond the gear box housing said body portion having an opening therein concentric with the fuel supply conduit, means to connect said extension of the body portion of the gear with the screw conveyor comprising a pin member insertable through said extension and the screw conveyor shaft and a source of power adapted to rotate the gears.

6. In a stoker of the underfeed type, a fuel conveying conduit formed of a plurality of sections, means to connect said sections to form a continuous passage for the fuel, a'screw con- ,veyor in said conduit, a gear box having gears therein positioned intermediate of the ends of the conduit, a rotatable sleeve mounted in said gear box, said sleeve being formed with a gear member on the periphery thereof and an integral extended portion projecting beyond the gear box casing, means to connect said rotatable sleeve with the screw conveyor comprising a pin member insertable through the extension formed on the sleeve and the screw conveyor shaft and a source of power adapted to rotate the sleeve.

'7. In a stoker of the underfeed type, a fuel conveying conduit formed of a plurality of sections, means to connect said sections to form a continuous passage for the fuel, comprising coupling sleeves, one of said sleeves being rotatably mounted in the fuel conduit, said rotatable sleeve being formed with an interior spiral adapted to move the fuel longitudinally thereof when the sleeve is rotated, a screw conveyor in said conduit, means to connect the conveyor with the rotatable sleeve and a source of power adapted to rotate the sleeve.

8. In a stoker of the underfeed type, a fuel conveying conduit formed of a plurality of sec; tions, meansto connect said sections to form a continuous passage for the fuel, comprising coupling sleeves, one of said sleeves being rotatably mounted in the fuel conduit, said rotatable sleeve being formed with an interior spiral adapted to move the fuel longitudinally thereof when the sleeve is rotated, a screw conveyor in said conduit, means to connect the conveyor with the rotatable sleeve comprising a pin member insertable through said sleeve and the screw conveyor shaft and a source of power adapted to rotate the sleeve. 9. In a stoker of the underfeed type, a fuel conveying conduit formed of a plurality of sections, means to connect said sections to form a continuous passage for the fuel, comprising coupling sleeves, one of said sleeves being rotatably mounted in the fuel conduit, said rotatable sleeve being formed with an interior spiral adapted to move the fuel longitudinally thereof when the sleeve is rotated, a screw conveyor comprising a plurality of sections in said conduit, means to connect the rotatable sleeve to the ends of two of the sections, comprising pin members insertable through the sleeve and the shafts of the screw conveyor sections and a source of power adapted to rotate the sleeve.

IEASCIUALEv FRICCHIONE. 

